There is a competition I am entering and the closing date is tomorrow (the 3rd of November). Does that mean they won't accept any of the entry's tomorrow or will tomorrow be the last day they accept entry's? (It is an art competition.)
There is a built-in ambiguity in such questions. Here is an example:-
Pick a number between 1 and 20
Are we supposed to include 1 and 20? I think most people would understand it to include numbers 1 and 10.
But with time the ‘boundary problem’ is trickier.
Sugar Fans sweet shop is open from 9am to 5pm Monday to Friday.
Strange. There seems to be no doubt that the shop opens at 9 and closes at 5. It does not mean that it will be open throughout each hour between 9 and five. It closes at five.
But we take the opposite view of the days of the week. Being open from Monday to Friday does not mean that the shop will be closed from the beginning of Friday till the beginning of Monday.
But many people share your uncertainty about an offer or completion or tax return deadline. My feeling is that most people would understand deadline dates to include the whole of the final day.mo
If I were entering a competition i or my tax returns, and if I were unsure, I should take the cautious view and not wait for the final day!
At the same time anyone giving a range of dates can remove all doubt by using the word inclusive
The competition is open from the 10th to the 19th Dec inclusive. Or. ...exclusive
So if there is a rule here, it is to the writer to pay attention to the reader.